Method and apparatus for filling a container with fiber

ABSTRACT

An apparatus for filling containers with loose fill material, comprising an opener for opening the fill material into a separated condition suitable to be injected into the container. A blower communicates with the opener for entraining the opened fill material in a pressurized air stream, and a nozzle communicates with the blower for directing the pressurized air stream and entrained fill material into the container. An air pressure gauge operatively communicates with the pressurized air stream for determining the pressure in the air stream and an increase in air pressure indicative of a predetermined amount of fill material in the container. A flow controller communicates with the pressurized air stream for starting and stopping the injection of fill material into the container.

TECHNICAL FIELD AND BACKGROUND OF INVENTION

This invention relates generally to filling containers with staple fiber entrained in a moving air stream. More particularly, the invention relates to filling items such as pillows and cushions with staple fiber entrained in a moving air stream, such as in a manufacturing process wherein bedding, furniture and similar products are made. For the purpose of illustration and explanation, the invention of this application is described with relation to the filling of a pillow with a predetermined quantity of fill material. It will be understood that when the term “container” is used, it is used in the sense of a flexible case, envelope, bag or the like, usually formed of fabric, in which the fill material is contained, and which increases in volume as the fill material enters the container. A pillow is one such “container.” The term “tick” is a term of art that refers to a fabric envelope, such as a pillow, that is left with an opening of sufficient size through which to inject the fill material. The opening is then closed to permanently encapsulate the fill material in the envelope.

Pillows, cushions, duvets, comforters, insulated apparel and the like can be filled with a variety of fill materials, including staple fibers, chopped feathers, down, and chopped, shredded or granulated foam. At present, pillows are filled by one of two principal methods-weight or the size assumed by the container with an amount of fill material therein.

Numerous devices exist that weigh fill material for placement in a container. In many cases, the fill material is entrained in a moving air stream, and injected into the container, with the air exiting the container through the fabric openings. These devices may be quite accurate, but require an amount of time to dispense and weigh the fill material, during which the filling process cannot occur. Other devices allow weighing to occur in two out-of sequence steps so that one batch of fill material can be inserted into a container while another batch of fill material is being weighed. These systems are relatively slow, complex and expensive.

Operators with substantial experience are often able to fill a container merely by feel and observation with a relatively high degree of accuracy. The operator fills the container by inserting a blower nozzle into an opening in the container and observing the increase in size and volume as the container fills. The container is evenly filled by moving the container relative to the nozzle so that fill material is blown into all parts of the container. However, such operators are in short supply, and a change in pillow or cushion size, shape or fill density can result in a large amount of wasted time and material before the operator is sufficiently trained to a proper level of consistency. Of course, it is important to achieve a high degree of fill accuracy, since the amount of fill material in the container ultimately translates into the size, shape and density of the resulting pillow or cushion.

The invention disclosed and claimed in the invention is based on the development of a fill apparatus and method that takes into account that as a container is filled, the back air pressure upstream of the container responds in a predictable manner to the amount of fill material in the container. By determining the air pressure correlative to a particular amount of fill material in a particular container, like containers can be consistently filled to an acceptable degree of accuracy by monitoring the air pressure and ceasing the introduction of fill material into the container at the appropriate air pressure.

SUMMARY OF THE INVENTION

Therefore, it is an object of the invention to provide a simple, effective and inexpensive way of accurately filling pillows, cushions and other filled containers with a fill material entrained in a moving air stream.

It is another object of the invention to provide an apparatus for filling pillows, cushions and other filled containers with fill material such as staple fibers to a predetermined fill density based on the pressure of the air in which the fill material is entrained.

It is another object of the invention to provide a method for filling pillows, cushions and other filled containers with fill material to a predetermined fill density based on the pressure of the air in which the fill material is entrained.

These and other objects and advantages of the present invention are achieved by providing an apparatus for filling containers with loose fill material, comprising an opener for opening the fill material into a separated condition suitable to be injected into the container. A blower communicates with the opener for entraining the opened fill material in a pressurized air stream, and a nozzle communicates with the blower for directing the pressurized air stream and entrained fill material into the container. An air pressure gauge operatively communicates with the pressurized air stream for determining the pressure in the air stream and an increase in air pressure indicative of a predetermined amount of fill material in the container. A flow controller communicates with the pressurized air stream for starting and stopping the injection of fill material into the container.

According to one embodiment of the invention, a fill material conveying manifold interconnects the opener and blower for receiving opened fill material from the fill material opener and conveying the fill material to the blower.

According to another embodiment of the invention, first and second spaced-apart blowers and nozzles are provided for permitting first and second separate container-filling operations to be carried out simultaneously and independently.

According to another embodiment of the invention, the shut-off comprises a shut-off gate operatively associated with the flow controller and positioned intermediate the blower and the manifold.

According to another embodiment of the invention, the shut-off comprises first and second shut-off gates for permitting the flow of air-entrained fill material to be individually interrupted during two simultaneous and independent container-filling operations.

According to another embodiment of the invention, the pressure gauge includes a visual indicator of the air pressure in the pressurized air stream.

According to another embodiment of the invention, the pressure gauge operatively communicates with the pressurized air stream downstream of the blower and upstream of the nozzle.

According to another embodiment of the invention, the flow controller includes a shut-off device for stopping the injection of air-entrained fill material into the container in response to a predetermined increase in air pressure.

According to another embodiment of the invention, the flow controller includes a manually-operated device for stopping the injection of air-entrained fill material into the container in response to a predetermined increase in air pressure.

According to another embodiment of the invention, the flow controller includes an automatic shut-off for stopping the injection of air-entrained fill material into the container in response to a predetermined increase in air pressure.

According to another embodiment of the invention, the container comprises a flexible fabric bag-like structure such as a pillow or cushion.

According to another embodiment of the invention, a fiber dispensing control apparatus is provided for controlling the flow of air-entrained fiber from a fiber supply system into a container, and comprises an air pressure gauge adapted to communicate with the fiber supply system for determining the air pressure within the fiber supply system, and a flow controller operatively associated with the air pressure gauge and responsive to an increase in the air pressure within the fiber supply system indicative of a predetermined amount of fiber in the container.

According to another embodiment of the invention, a manually-operated device is provided for starting the flow of fiber into the container.

According to another embodiment of the invention, a manually-operated device is provided for stopping the flow of fiber into the container.

According to another embodiment of the invention, an automatically-operated device is provided for stopping the flow of fiber into the container.

According to another embodiment of the invention a method of dispensing fill material entrained in a moving air stream into a container is provided, and comprises the steps of determining an air pressure within the moving air stream indicative of a predetermined amount of fill material in the container, sensing the air pressure within the fill material supply system; and sensing the increase in the air pressure within the moving air stream indicative of a predetermined amount of fill material in the container. The flow of fill material into the container is then stopped.

According to another embodiment of the invention, the method includes the step of stopping the flow of fill material into the container includes the step of automatically stopping the flow of fill material into the container.

According to another embodiment of the invention, the method includes the step of providing an alarm indicative of a predetermined amount of fill material in the container, wherein the step of stopping the flow of fill material into the container comprises manually stopping the flow of fill material into the container by an operator in response to the alarm.

According to another embodiment of the invention, the alarm is an audible or visual alarm.

According to another embodiment of the invention, the fill material is selected from the group consisting of staple fibers, chopped feathers, down, foam or plastic.

BRIEF DESCRIPTION OF THE DRAWINGS

Some of the objects of the invention have been set forth above. Other objects and advantages of the invention will appear as the invention proceeds when taken in conjunction with the following drawings, in which:

FIG. 1 is a perspective view of one embodiment of the apparatus for filling a container, such as a pillow, with a quantity of fill material;

FIGS. 2, 3 and 4 are perspective views based on FIG. 1 showing the method of filling the pillow with the apparatus shown in FIG. 1;

FIG. 5 is a schematic view of one pressure gauge device that may be used as a part of the filling apparatus; and

FIG. 6 is a flow diagram of one embodiment of the method in accordance with the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT AND BEST MODE

Referring now specifically to the drawings, an apparatus according to a preferred embodiment of the invention is shown at broad reference numeral 10, and includes a fiber opener 12, for example, a Fiber Controls staple fiber opener. One typical staple fiber suitable for use is a 1.5 inch staple, 7 denier polyester fiber. As noted above, many other fibers, synthetic and natural, as well as other materials such as feathers, down and foam are also suitable for use with this method, although the manner of processing the materials for being entrained in the air stream may differ.

The opener 12 separates the fibers, which are typically in large clumps, and prepares them for being introduced into a moving air stream. After opening, the fibers are conveyed into a manifold 14 that is connected to a pair of blowers 16, 18. Flow of fibers from the opener 12 and manifold 14 to the blowers 16, 18 is controlled by a pair of shut-off, or “blast” gate assemblies 20, 22 positioned between the manifold 14 and the respective blowers 16, 18. The shut-off gate assemblies 20, 22 are operated by respective pneumatic cylinders 24, 26 that move internal gates (not shown) vertically to either allow or interrupt the flow of air and the entrained fibers from the manifold 14 into the blowers 16, 18.

The provision of two blowers 16, 18 from the manifold 14 allows two operators to fill from a single apparatus 10, but is optional. For this reason, further explanation of the invention refers only to the function of blower 16 and related machine elements, it being understood that the same explanation applies equally to the blower 18 and its related machine elements, shown but not further identified or explained.

The blower 16 is a conventional type used in fiber processing, and generally operates between 500-1500 CFM at 3400 rpm and 45 Hz. The blower 16 has a staple fiber delivery capacity of about 1,000 lbs/hr. A transition fitting 30 delivers air and entrained fibers from the blower 16 to a fill nozzle 32 that is positioned over a work table 34. A pressure sensor 36 in the transition fitting 30 sensing air pressure and conveys the data to a pressure gauge and shut-off device 38 that is conveniently mounted, for example, between the shut-off gate 20 and blower 16 where it is easily visible to an operator standing at the work table 34. A flow controller, for example, a foot pedal 40 connected to the shut-off gate 20 through the pressure gauge and shut-off device 38, permits the operator to manually open and close the shut-off gate 20 to start or stop the flow of fiber into the blower 16. This system is a PLC based control system. All control devices interface directly with the PLC as input or output devices. The logic program in the PLC evaluates the inputs and directs the outputs accordingly. For example, the pressure transmitter will indicate to the PLC logic that shutoff pressure has been reached. In response, the PLC will disengage the output which shuts the shut-off gate 20. The pressure gauge and shut-off device 38, foot pedal 40, shut-off gate assemblies 20, 22 and all motors are controlled by the PLC.

In one preferred embodiment of the invention, it is determined empirically that air pressure in the transition fitting 30 is approximately 5 psi during the filling process, and as the pillow becomes sufficiently densely filled so that the fill material itself begins to hinder passage of air out of the fabric, the pressure increases slightly, to about 5.5 psi. In this example, this translates to a filling weight of polyester staple fiber of about 30 oz. It has been determined that the air pressure change as described above occurs relatively rapidly, and if the flow of fill material is shut off at the same elevated air pressure, in this case, 5.5 psi, the weight of fill material in the pillow is very nearly the same in each instance, on the order of plus or minus 10 percent or less.

As shown in FIG. 2, the container, in the example shown, a pillow, is placed onto the end of the nozzle 32. Then, as shown in FIG. 3, the shut-off gate 20 opened by depressing the foot pedal 40. As fiber is blown into the pillow, the pillow is moved back and forth to promote even filling. When the pillow reaches the proper degree of filling, as shown in FIG. 4, the shut-off gate 20 is closed, for example, by again depressing the foot pedal 40.

The shut-off gate 20 may be closed at the proper time in one of several ways. As is shown in FIG. 5, the pressure gauge and shut-off device 38 may include a needle 42 that indicates air pressure. When the needle 42 moves to the set point, the operator depresses the foot pedal 40 to close the shut-off gate 20.

The pressure gauge and shut-off device 38 may also include an alarm in the form of, for example, a series of lights 44 that illuminate as the pressure increases, allowing the operator to observe the filling progress with “lead time” indicated by the lights 44 to permit the operator to depress the foot pedal 40 exactly as the pressure reaches the desired shut-off point. An audible alarm may be provided in addition to the visual alarm, or in place of the visual alarm.

Alternatively, the pressure gauge and shut-off device 38 may include an automatic shut-off so that the shut-off gate 20 closes without operator intervention when the pressure set point is reached.

FIG. 6 summarizes the method according to one preferred embodiment of the invention, described above, with reference to the filling of a “tick”, i.e. a fabric envelope with an opening left for introduction of the nozzle 32.

As noted above, the proper set point is determined by filling several pillows, cushions, etc. to the proper degree of fill, while observing and recording the change in air pressure in the transition fitting 30 as this occurs. From this process, the pressure at which the pillow is properly filled can be determined. This pressure is used to either instruct the operator when to close the shut-off gate 20, or to set the pressure gauge and shut-off device 38 to automatically close the shut-off gate 20. The pressure shut-off point is defined in the PLC. The pressure set point is entered via a color touch panel human machine interface (“HMI”). All operational set points are entered via the HMI. The HMI provides a textual/graphical interface and provides for all set point entry and specific alarm indication as well as operational status and motor control settings. The HMI device is the interface between the operator and PLC.

An improved method and apparatus for filling a container with fiber is described above. Various details of the invention may be changed without departing from the scope of the invention. Furthermore, the foregoing description of the preferred embodiment of the invention and best mode for practicing the invention are provided for the purpose of illustration only and not for the purpose of limitation, the invention being defined by the claims. 

1. An apparatus for filling containers with loose fill material, comprising: (a) an opener for opening the fill material into a separated condition suitable to be injected into the container; (b) a blower communicating with the opener for entraining the opened fill material in a pressurized air stream; (c) a nozzle communicating with the blower for directing the pressurized air stream and entrained fill material into the container; (d) an air pressure gauge operatively communicating with the pressurized air stream for determining the pressure in the air stream and an increase in air pressure indicative of a predetermined amount of fill material in the container; and (e) a flow controller communicating with the pressurized air stream for starting and stopping the injection of fill material into the container.
 2. An apparatus according to claim 1, and including a fill material conveying manifold interconnecting the opener and blower for receiving opened fill material from the fill material opener and conveying the fill material to the blower.
 3. An apparatus according to claim 2, and including first and second spaced-apart blowers and nozzles for permitting first and second separate container-filling operations to be carried out simultaneously and independently.
 4. An apparatus according to claim 2, wherein the shut-off comprises a shut-off gate operatively associated with the flow controller and positioned intermediate the blower and the manifold.
 5. An apparatus according to claim 3, wherein the shut-off comprises first and second shut-off gates for permitting the flow of air-entrained fill material to be individually interrupted during two simultaneous and independent container-filling operations.
 6. An apparatus according to claim 1, wherein the pressure gauge includes a visual indicator of the air pressure in the pressurized air stream.
 7. An apparatus according to claim 1, wherein the pressure gauge operatively communicates with the pressurized air stream downstream of the blower and upstream of the nozzle.
 8. An apparatus according to claim 1, wherein the flow controller includes a shut-off device for stopping the injection of air-entrained fill material into the container in response to a predetermined increase in air pressure.
 9. An apparatus according to claim 1, wherein the flow controller includes a manually-operated device for stopping the injection of air-entrained fill material into the container in response to a predetermined increase in air pressure.
 10. An apparatus according to claim 1, wherein the flow controller includes an automatic shut-off for stopping the injection of air-entrained fill material into the container in response to a predetermined increase in air pressure.
 11. An apparatus according to claim 1, wherein the container comprises a flexible fabric bag-like structure such as a pillow or cushion.
 12. A fiber dispensing control apparatus for controlling the flow of air-entrained fiber from a fiber supply system into a container, comprising: (a) an air pressure gauge adapted to communicate with the fiber supply system for determining the air pressure within the fiber supply system; and (b) a flow controller operatively associated with the air pressure gauge and responsive to an increase in the air pressure within the fiber supply system indicative of a predetermined amount of fiber in the container.
 13. A fiber-dispensing control apparatus according to claim 12, and including a manually-operated device for starting the flow of fiber into the container.
 14. A fiber-dispensing control apparatus according to claim 12, and including a manually-operated device for stopping the flow of fiber into the container.
 15. A fiber-dispensing control apparatus according to claim 12, and including an automatically-operated device for stopping the flow of fiber into the container.
 16. A method of dispensing fill material entrained in a moving air stream into a container, and comprising: (a) determining an air pressure within the moving air stream indicative of a predetermined amount of fill material in the container; (b) sensing the air pressure within the fill material supply system; (c) sensing the increase in the air pressure within the moving air stream indicative of a predetermined amount of fill material in the container; and (d) stopping the flow of fill material into the container.
 17. A method according to claim 16, and the step of stopping the flow of fill material into the container includes the step of automatically stopping the flow of fill material into the container.
 18. A method according to claim 16, and including the step of providing an alarm indicative of a predetermined amount of fill material in the container, wherein the step of stopping the flow of fill material into the container comprises manually stopping the flow of fill material into the container by an operator in response to the alarm.
 19. A method according to claim 18, wherein the alarm is an audible or visual alarm.
 20. A method according to claim 18, wherein the fill material is selected from the group consisting of staple fibers, chopped feathers, down, foam or plastic. 